The present invention relates generally to a method and system for providing adaptive modulation/coding and adaptive power allocation in a communication system and, more particularly, to a method and system for providing adaptive modulation/coding and excess resource distribution in accordance with one or more desired system criteria.
Adaptive modulation/coding (AMC) is a link adaptation method that has been employed in telecommunication systems to improve system performance. With AMC, users with high carrier to interference (C/u) ratios enjoy high data rates that contribute significantly to system capacity. Conversely, users that have a poor C/I require a much lower data rate. Unfortunately, current AMC methods have two limitations. First, a number of users may not have a sufficient C/I to support the lowest of the modulation/coding rates (MCRs) in the system. These users are unable to access the system, and as a result, the system coverage reliability is reduced. Second, the current AMC methods do not make the most efficient use of the available transmit power because users are normally assigned an MCR that has a lower C/I requirement than the actual C/I of the user.
Accordingly, there is a need for a method and system which implements a link adaptation method which achieves relatively high system capacity and system coverage and which provides flexibility to modify the link adaptation method to achieve a number of different system criteria.